Process for smelting ores



1,51 BBUG Nov. m; 11924.

J. R. STEEL PROCESS FOR SMELTING ORES Filed May 4, 92l

ATTK

Patented l lg@...

PROCESS FOR SMEJLTING ORES.

Application filed 'May 4,

Te all whom it may concewt:

Be it known that ll, JOHN lt. Sirin, a citizen of the United States, residing in the city and county of San Francisco and State tt of California, have invented new and useful llmprovements in Processes for Smelting Ores, of which the following is a specifieation.

This invention relates to a process for ll@ smelting ores, particularly ores of the iron group; and one object is to provide a method for reducing the ores by subjecting the ore to the intense heat which is Secured by burning hydrocarbons and pure oxygen gas within afurnaee. Another object of the invention is to provide a method of the character described which pernits the production either of pig iron, cast iron, wrought iron or steel in one operation. lFurther objects will hereinafter appear.

A standard type of blast furnae'e is illustrated in the accompanying drawing as such a furnace is suitable for conducting the presen'tprocess.

In treating ores of the iron group, it is usual to first roast the ore in order to decompose the carbonates and oxidize the sulphides, the ore being then reduced with coke. Ores containing lime or magnesia are mixed with an acid flux, such as sand or elay sla-te,.in order that a tusible slag may 'be iormed; Conversely, ores containing siliea and clay are mixed with limestone.

With aturnace construeted as shown in the accompanying drawing, it becomes possible to earry .on the' process continuously as the' solid materials may be thrown in at the to of the furnace from time to time. The w ole .mass of ore slowly descends and 'gradually liberates the gases which escape and liquids (iron and slag) which are tapped ofi'at the bottom.. lln Operating an llltl dil . ordinary blast furnaee it is necessary to mix the ore with a certain amount of coke to 'tt support combustion and it is also necessa -to turce heated air through tuyeres forme near the bottom of the furnaceto maintain an induced draft at all times.

ile the present process might .be more r otthe type shown, usng as a fuel nothing but crude. oil 'and pure oxygen gas; The

ecientlyoperated in another turnace, have' so :tar suecessfully employed a fumace I 1921. Serial No. 466323.

burner of any suitable Construction and the 55 gas and oil are injected through the tuyres shown directly into the ore body'. An enormous temperature is in this manner produced which rap-idly reduees the ore.

In Operating a furnace fed by fuel consist- 60 mg of oil and oxygen gas l discovered that by varying the quantity of oxygen gas admitted it was possible to produce different products, to-w'it, pig iron, cast iron, wrought iron and steel. A comparatively small W amount of pure oxygen gas admitted produces pig iron, while a gradual increase in the amount of oxygen gas employed produces east iron, wrought iron. and steel. I a also found that difl'erent grades of steel "t could be obtained, as the pure oxygen gas admitted seemed to reduce the earbon contents of the steel so that practieally any percentage desired might be obtained merely -by varying the olume of oxygen gas ad- W 'mitted I am aware that many attempts have been .made to reduce iron ore by employing erude oil as a fuel, but these attempts have all been more or less failures. Most of the' pig t@ iron produced when 'employing crude oil as a fuel seems tobe too spon and contains too much earbo'n, silica, p osphorus and sulphur. This defect is entirely overcome in the present instance as the carbon, silica tt and phosphorus combine with the oxygen of r the oxide, the last two passing into the slag and the sulphur being generally found in the slag as a ferrous sulphide.

The pure oxygen gas employed with my to process is the essential element for the successful production of the difl'erent products as it permits the manufaeture of steel in one operation directly from' the ore or any other grade of iron from the pure pig and` up.

ile an ordinary blast furnace and a burner which permits mixing of oil and oxygen gas are here shown, ll wish it understood that y suitable form of furnaee may be employed and that the fuel oil and oxygen to@ gas may be separately introdueed, if desired. Having thus described my invention, what ll claim and desire to secure by Letters Patent is-.

1. A process of -smelting ores, which con- 1105 sists in subjecting the ore to heat` produced by eombustion of a hydroearbon fuel and oxygen gas.

2. A process' for smelting ores, which con- V In testimony whereof I have hereunto set sist in subjecting the ore. to the direct flame my hand-in the presence of two subscribng 1 of bning oil and oxygen gas. witnesses.

3. process for producin cast iron c 5 wrought iron or steel directly rom an iron JOHN STEEL' ore, which consists in subjecting the ore to Witnesses: the .direct flame of burning oil and oxygen W. W. HEALLY,

gas. M. E. IRVING. 

